Water tube construction for down-the-hole drills



R. L. THOMPSON Oct. 30, 1962 I WATER TUBE CONSTRUCTION FOR DOWN-THE-HOLE DRILLS Filed June 11, 1958 2 Sheets-Sheet 1 ms ATTORNEY N R 0 m5. 6 NP WW :1 m T LY TB 2 m w. B 0 //V% R 2 i 6 I F a Q. Mn 3 w I 6% f in 9 /AQ MW mow I m 8 w 6 Oct. 30, 1962 R. L. THOMPSON 3,

WATER TUBE CONSTRUCTION FOR DOWN-THE-HOLE DRILLS Filed June 11, 1958 '2 Sheets-Sheet 2 #92 -zs f 67 I02 I00 96 I14 I06 H2 us Ho 2 I08 F/GQ8 INVENTOR ROBERT L. THOMPSON HIS ATTORNEY Unite grates This invention relates to improvements in rock drills, and more particularly to rock drills of the down-thehole type.

In drilling operations with such types of drills it has been common practice to use air as the cleansing fluid supplied into the hole being drilled to remove the earth cuttings. However it would greatly contribute to obtain better results in drilling operations, if a selection of cleansing fluids such as water or air or a mixture of water and air, or moreover, a proportioning of the waterair mixture, was available according to the formation encountered. In view thereof, a new type drill has been constructed in which not only an adequate amount of cleansing fluid is conducted through the drill unit but in which in addition thereto a selection of fluids and proportioning thereof to form a desirable cleansing fluid may be made to achieve cleansing of the hole being drilled.

It is, accordingly, an object of this invention to provide a rock drill of the down-the-hole type having means to supply an adequate amount of cleansing fluid into the hole being drilled.

Another object of the invention is to provide a rock drill having means to cleanse the hole being drilled selec* tively with air or water or with a mixture of water and air.

Still another object of this invention is to provide a rock drill having means for proportioning the water and air to be used as a cleansing fluid.

Another object of the invention is to provide a rock drill having means to conduct motive fluid and cleansing fluid separately through the rock drill unit.

Another object of the invention is to provide a rock drill with a drill shaft within which motive fluid and cleansing fluid are separately conducted.

Another object of the invention is to provide a rock drill unit having connections between its various ele ments adapted to conduct motive fluid and cleansing fluid separately therethrough.

Still another object of the invention is to provide such connections to be simple, inexpensive and reliable for continuous operation.

These and other objects and features of the invention will be apparent from the following specification when read in conjunction with the accompanying drawings wherein:

FIGURE 1 shows a longitudinal section of a part of the rotary motor, a tubular section and a part of the drill motor,

FIG. 2 is a continuation of FIGURE 1 showing in longitudinal section the other part of the drill motor,

FIG. 3 is a cross sectional view along the line 33 of FIGURE 1 looking in the direction of the arrows, showing the main supply line for cleansing fluid and an air line and Water line,

FIGS. 4, and 6 are cross sectional views of FIG. 1 taken along the lines 4-4, 5-5 and 66, respectively, and looking in the direction of the arrows,

FIG. 7 is a diagrammatic view showing the rock drill as a unit, and

FIG. 8 is a cross sectional view of a connection between two tubular sections.

Referring to the drawings for a description of a pre- 3,061,024 Patented Oct. 30, 1962 ice,

ferred embodiment of the invention, FIG. 7 shows diagrammatically a rock drill unit 20 including a downthe-hole type drill motor 22 inserted in a drillhole 27. The drill motor 22 is rotated by a rotary motor 24 which is actuated by a supply of compressed air from a suitable source (not shown). The rotary motion developed by the rotary motor 24 is transmitted to the drill motor 22 through a drill shaft 26 generallycomprising a plurality of tubular sections 28 connected to each other in end to end relation.

As the drill motor 22 is of the down-the-hole percussive type and operates inserted in a drill hole 27 the compressed air to operate the drill motor 22 as well as the cleansing fluid for cleansing the drill hole 27 according to the invention, are required to be conducted from the rotary motor 24 through the drill shaft 26 into the drill motor 22. In view thereof, it is important to conduct the compressed air and the cleansing fluid separately through the drill unit 20. This is achieved by the following arrangement.

The rotary motor 24 is provided with a connector 30, see FIG. 7, to which the drill shaft 26 is connected in end to end relation. A common type swivel fluid connection 32, see FIGS. 1 and 7, is arranged around the periphery 33 of the forward end of the connector 30 through which cleansing fluid is supplied to the unit 20, and a supply line 34 comprising an air line 36 and a water line 38, see FIG. 7, serves to conduct both fluids into the unit 20. The connector 30 is rotated by the rotary motor 24, however, by reason of its construction the cleansing fluid supply line 34 including its swivel type connection 32 to the connector 30 is held stationary relative to the connector 30. It is to be noted that the flow of each fluid may be regulated by the provision of valves 40 and 42 to selectively permit either one fluid or both fluids in any proportion to be conducted as a cleansing fluid into the hole 27 'being drilled.

The tubular sections 28 which form the drill shaft 26 are threadedly connected to each other in end to end relation, a connection 44 between two tubular sections 28 is shown in detail in FIG. 8. The drill motor 22 is threadedly connected to the drill shaft 26 through a connection 45, and the rotary motor 24 is threadedly connected to the drill shaft 26 through a connection 46, both connections being shown in detail in FIG. 1. The connections 44, 45 and 46 will be explained hereinafter.

Referring to the connection 46 and the arrangement of separately conducting compressed air and cleansing fluid through this connection, the connector 30, in its forward end portion is provided with a longitudinal central bore 48 from which radial passages 50 lead to the periphery 33 of the connector 30 and registering with the supply line 34. Within this bore 48 a tube 52 having a collar 54 is inserted and held in place by a common gland 56 and packing 58 arrangement. The tube 52 extends into the rear end portion of a tubular section 28 in which a closure plug 60 is provided having a bore 62 therethrough with a diameter adapted to slidably receive the tube 52. A rubber O-ring 64 recessed in the wall of the bore 62 insures a leak-proof seal of the tube 52 in the bore 62 of the closure plug 60. As shown in FIG. 1, the connector 30 is provided with a main passage forward end of the connector 30. tudinal passages 66 through the closure plug 60 is pro vided to conduct air from the forward end of the connector 30 to the interior 67 of the tubular section 28.

Referring to the connection 45 and the arrangement of separately conducting compressed air and cleansing fluid through this connection, the forwardend portion of the tubular section 28 is provided with a closure plug 72 having a central bore 78 in which a tube 74 with a collar 76 is held in place by a gland 80 and packing 82 arrangement. The tube 74 extends into the rear end portion of the drill motor 22 which is provided with a central bore 84 adapted to slidably receive the tube 74. A rubber O-ring 86 recessed in the wall of the bore 84 insures a leak-proof seal of the tube 74 in the rear end portion of the drill motor 22. The closure plug 72 is provided with longitudinal passages 88 communicating the interior 67 of the tubular section 28 and a passage 90 in the drill motor 22, the passage 90 serving to conduct the compressed air into the drill motor 22 for op eration thereof.

As shown in FIGURE 1, a flexible hose 92 connects the bore 62 of the rear closure plug 60 of the tubular section 28 with the bore 78 of the forward closure plug 72 of the tubular section 28. The connection of the rear end of the flexible hose 92 with the bore 62 and the connection of the forward end of the flexible hose 92 with the bore 78 is achieved by the common type threaded hose nipple 94 connection. With this construction in each tubular section 28 the cleansing fluid is conducted through the flexible hose 92 while the compressed air flows around the flexible hose 92 through the interior 67 of the tubular section 28 which arrangement provides for a separate conductance of the compressed air and the cleansing fluid through each tubular section 28. One of the features of using a flexible hose 92 in the tubular sections 28 to conduct the cleansing fluid therethrough separately from the compressed air is that the hose 92 will withstand any vibration that is produced during drill operations.

The assembly in each tubular section 28 of the rear closure plug 60, the forward closure plug 72, and the flexible hose connecting both closure plugs is as follows. First, one end of the flexible hose 92 is connected to the closure plug 60 by threading the nipple 94 into the forward end portion of the bore 62, the closure plugs 60 and 72 not yet inserted into the associated end portions of the tubular section 28, and the tubular section 28 being disconnected from connector 30 and drill motor 22. Secondly, the unconnected end of the hose 92 is lead through the interior 67 of the associated tubular section 28 whereafter the closure plug 60 is fitted in its operating position into the rear end portion of the tubular section 28, as described hereinafter. It is to be noted that the rear end portion of tubular section 28 is slightly tapered such to receive closure plug 60 which is correspondingly slightly tapered, the latter being pressed into the rear end portion of section 28 to form a fluid tight and detachable fitting between the closure plug 60 and its associated rear end portion of tubular section 28. Then, the nipple 94 of the unconnected end of the hose 92 is threaded into the rear end portion of the bore 78 in the closure plug 72. It is to be noted that the hose 92 is to be long enough to provide, for suflicient slack to achieve this threaded, connection, in other words, when the closure plug 60 is fitted in its operating position the forward end of the hose 92 should extend slightly further than the forward end of the tubular section 28. After threading the unconnected end of the. hose 92 to the closure plug 72 the assembly is completed by fitting the closure plug 72 in its operating position in the forward end portion of the tubular section 28, the closure plug 72 and the associated forward end portion of tubular section 28 having the same tapered relationship as hereinbefore described with respect to closure plug 60 and the associated rear end portion of tubular section 28. When the closure plug 72 is in its operating position the slack of the hose 92 will cause the hose 92' to coil slightly in the interior 67 of. the tubular section 28, which is considered advantageous with respect tothe absorbing of vibration produced by the drilling operation.

As for the connection 44 between two tubular sections 28, FIG. 8 shows such a connection in detail in which the forward end of one tubular section 28 is provided with a closure plug 96 in which a tube 98 having a collar 100 is centrally positioned in a central bore 102 in said closure plug 96 and held in place by a common gland 104 and packing 106 arrangement. The tube 98 extends into the rear end of the next tubular section 28 in which is provided a closure plug 108 having a central bore 110 therethrough with a diameter adapted to slidably receive the tube 98. It is to be noted that the fluid tight and detachable fitting between the closure plugs 96 and 108 and the associated end portions of tubular sections 28 is achieved in the same manner as hereinbefore described in connection with the closure plugs 60 and 72. A rubber O-ring 112 recessed in the wall of the bore 110 in the closure plug 108 insures a leak-proof seal of the tube 98 in the bore 110. A passage 114 in the closure plug 96 and a passage 116 in the closure plug 108 cooperate to communicate the interior 67 of one tubular section 28 with the interior 67 of the other tubular section 28 for the conductance of compressed air from one tubular section to the next tubular section.

The drill motor 22 is of the common down-the-hole type comprising, a backhead 118, a cylinder 120 and a working implement 122 connected to the forward end portion of the cylinder 120. The cylinder 120 is bored to provide a piston chamber 124 for accommodating a hammer piston 126 actuated to strike the working implement 122. The hammer piston 126 is actuated by compressed air conducted from the rotary motor 24 through the drill shaft 26, through the passage 90 and ports 91 in the backhead 118 of the drill motor 22, and distributed by a valve mechanism 128 through the passages 130 and 132 to the ends of the piston chamber 124. The cleansing fluid is conducted through the drill motor 22 by a centrally positioned tube 134 extending from the rear end portion of the backhead 118 through the cylinder 120 and into the working implement 122. It is to be noted that the tube 134 is in communication with the tube 74 in the forward end portion of the tubular section 28.

Referring to the simplicity of the connections described hereinbefore, it is to be noted that whenever a tubular section 28 of the drill shaft 26 is threaded into the connector 30 of the rotary motor 24 the centrally positioned tube 52 of the connector 30 will automatically be received by the central bore 62 in the rear closure plug 60 of the associated tubular section 28 while the rubber 0- ring 64 will insure a leak-proof fit of the tube 52 in the bore 62. The other connections are achieved in a similar Way such that when forming a drill string there will be no difliculty in connecting the tubular sections 28 to each other While the separate conductance of cleansing fluid and air through each connection and through each tubular section 28 is achieved automatically.

It is to be understood that the invention is not to be limited to the specific construction or arrangement of parts shown, but that they may be modified within the invention defined by the claims.

I claim: a

1. In a rock drill having a rotary motor, a fluid operated drill motor having a Working implement operatively connected to its forward end, said drill motor and implement being insertable into the hole being drilled and having discharge passage means for cleansing fluid, a tubular shaft having one end connected to said rotary motor and the other end connected to said drill motor for rotating said drill motor and implement by said rotary motor, said shaft comprising a plurality of sections connected in end to end relation to conduct motive fluid and cleansing fluid. separately from the shaft .end adjacent the rotary motor to the drill motor, means for receiving motivefluid and cleansing fluid separately into the rear end of said shaft, a plug detachably fitted within each end portion of each tube section and having a through port to provide communication between the interiors of adjoining sections for the passage of one of such fluids, each plug having a through bore, a pipe at each tube section connection having one end releasably connected to one of the plugs of one section in communication with the bore thereof and having its other end automatically fitted within the bore in the plug of the other section when the sections are connected to each other, and a conduit in each tube section connected between the plugs of such tube section and in communication with such bores for the passage of the other of such fluids.

2. In a rock drill according to claim 1, in which said fluid receiving means is a connector at the forward end of said rotary motor connecting the rear end of the shaft to the motor to transmit rotary motion to said shaft, a passage in said connector to receive motive fluid and leading to the forward end thereof in communication with the interior of the adjoining tube section through the port in the plug, a longitudinal bore in said connector having its rear end closed leading to the forward end of said connector axially alined with the bore of the adjoining tube section, at least one radial passage from the periphery of said connector in communication with the longitudinal bore, means connected to the periphery of said connector in communication with said radial passage for supplying cleansing fluid and held against rotation with said shaft, and a pipe having one end in one of said axially alined bores and the other end automatically fitted into the other axially alined bore when the shaft is connected to the connector.

3. In a rock drill according to claim 1 in which each of said conduits are flexible so at least one plug may be inserted into each tube section after each conduit is connected at each of its ends.

4. In a rock drill having a rotary motor, a tubular shaft connected to one end of the motor and rotated thereby, a fluid operated drill motor connected to the other end of the shaft rotated by the rotary motor and having a passage for cleansing fluid, a working implement operatively connected to the drill motor and having a port in communication with the drill motor passage for discharging cleansing fluid, said shaft having a plurality of dual passage tubular sections connected in end to end relation to conduct motive fluid through one of said passages and cleansing fluid through the other of said passages unidirectionally therethrough, means to provide motive fluid at the rear end of said shaft to one of said passages, and means to provide cleansing fluid at the rear end of said shaft to said other of said passages, a connection between two adjoining tubular sections comprising, a first closure detachably inserted in one end portion of each tubular section, a second closure detachably inserted in the other end portion of each tubular section, each closure having a through port and a through bore to provide communication between the passages of adjoining sections when the sections are connected to each other, a pipe at each connection having one end releasably connected in the bore of one of the closures of one associated section and having its other end received in the bore of a closure in the other section when the sections are connected to each other, and passage means connected in the bores to the opposing ends of the first and second closures of each tubular section to provide communication between pipes connected in series to form one .of the passages of each section and the interiors of the tube sections communicating with the interiors of adjoining sections forming the other of said passages.

5. The drill according to claim 4 in which said passage means is a flexible tube having a length at least as great as the length of the associated tube section.

6. A shaft for transmitting rotary motion to a drill motor adapted to be inserted in a hole being drilled, and for separately supplying to the drill motor a cleansing fluid for cleansing the drill hole and a motive fluid for motor operation; said shaft comprising a plurality of tube sections connected in end to end relation, a plug removably fitted in each end portion of each of the tube sections and having a passage through each plug to provide communication between the associated tube section interiors to form a passage for the flow of one of such fluids, each plug having a through bore in communication with the bore in the plug in the adjoining section, and a flexible tube within each section connected at its ends to the bores in the plugs of the associated tube section to form another passage for the other said fluid, each flexible tube having a length at least as great as the distance between one end of the tube section and the inner end of the plug at the other end of the tube section.

7. A tubular device providing two fluid flow paths, comprising a tubular shell, a plug to be fitted into each end of the shell to form a wall at each shell end, each plug having a pair of openings therethrough one of which is in communication with the interior of the shell to provide the first fluid flow path therethrough when both plugs are fitted into the shell, and a flexible tubular member extending through the shell having each end connected in the other of said pair of openings of the plug at the adjacent shell prior to fitting both plugs into the associated shell ends to form the second fluid flow path, said flexible tubular member having a length greater than the length of the shell and being deformed by fitting both plugs into the shell.

References Cited in the file of this patent UNITED STATES PATENTS 1,005,770 Clark Oct. 10, 1911 1,053,621 McAllister Feb. 18, 1913 1,461,713 Gilman et al July 10, 1923 1,481,255 Cumfer Jan. 22, 1924 1,862,260 Edmunds June 7, 1932 1,868,400 Stover July 19, 1932 1,891,416 Harris Dec. 20, 1932 2,810,549 Morrison Oct. 22, 1957 2,818,230 Davis Dec. 31, 1957 2,850,264 Grable Sept. 2, 1958 

